[GreenKeys] Teletype monopulse printer

[Duncan M. Brown]

> [Original Message]
> From: John Nagle <nagle at animats.com>
> To: <greenkeys at mailman.qth.net>
> Date: 21-Nov-09 12:51:45
> Subject: Re: [GreenKeys] Teletype monopulse printer
>
>
>      Probably, the typewheel holds at the start point at the end of the
> cycle, so it resynchronizes once per character time.
>
>      Both ends have to rotate at the same speed, to within half a
character
> time.  The allowed speed error for that design is 0.5/(number of wheel 
> positions), which is about 1%.  Start-stop Teletypes will tolerate much
> more than that.  A 3% speed difference isn't even noticed, and 6% can
> be tolerated.  The governed Teletype motors were able to stay within
> those limits, but 1% would have been tough. A spring-loaded on/off
> governor switch speed control can only do so much.
>
>
> 					John Nagle
>

John,

I hadn't thought about it in that way.  I agree, 1% could have been hard to
achive.  I noticed in one of Brooke's pictures a "Synchronization" control
of some sort.

have fun,

  Duncan